The invention relates to methods of verifying and authenticating printed articles, in particular methods of verifying and authenticating thermally-imageable printed articles such as venue tickets, pharmaceutical prescription container labels, and the like.
Differentiating genuine articles from fakes or frauds has become an important part of modern business. It is estimated that millions of dollars of business are lost yearly due to the passing off of counterfeit items as genuine articles. The problem spans a wide variety of industries, including travel and entertainment, which use printed tickets subject to counterfeiting; and manufacturing and service industries, in which fake or substandard articles (as widely varied as compact discs, computer software, pharmaceutical prescriptions, etc.) are marked for sale with labels imitating the original. The presence of fake goods in the marketplace results in significant losses of money and goodwill to vendors, as well as detriments to consumers. Customers may be harmed when purchasing fake goods which are passed off as those produced by a well-known manufacturer because they believe they are paying for genuine goods when in fact they may be receiving substandard goods. Additionally, if the customer attempts to return or exchange defective goods under warranty, he may find he cannot because the manufacturer will not honor the warranty. Therefore, as fake and falsely-labeled articles continue to enter specific markets, the need for verification methods and systems which enable consumers, retailers, manufacturers, etc. to identify genuine articles has become more pointed.
Thermally-imageable substrates such as thermal paper have many applications. These "direct thermal" papers have been used in great volume in document printers and fax machines. However, as ink jet and electrostatographic printing technologies have diminished the use of direct thermal papers, direct thermal has found a niche as the printing mode of choice for applications where variable information on demand is needed, such as airline tickets and boarding passes, luggage tags, parking tickets, venue tickets such as concert and theater tickets, lottery receipts, point of sale receipts, and pharmaceutical and grocery labels.
A distinct benefit of direct thermal is that no ink or ribbon needs to be replenished in the printers and the coated thermal paper is relatively inexpensive. However, counterfeiting of lottery tickets, gaming tickets and concert tickets present a significant revenue loss to these industries. These articles are simply photocopied and sold as the genuine article. Also, in retail stores, receipts have been known to be photocopied and then resubmitted by the unscrupulous for refunds on merchandise that were never purchased. Furthermore, since thermal printing apparatus and paper is widely available, it is also relatively easy to produce counterfeit thermally-printed articles, and it is difficult to determine a fake thermally-printed article from genuine article.
Various solutions to the problem, i.e., use of holographic labels, watermarks, etc. have been proposed. However, it is difficult to print such labels by conventional means, and the labels cannot be used in thermal printing apparatus.
It is therefore an object of this invention to provide methods of authenticating printed articles such as labels, tickets, or lottery stubs by imparting special optical properties to the printed surfaces thereof, and systems which enable such authentication methods to be practiced.